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Waste water treatment

water that has been used in homes, industries, and businesses that is not for reuse unless it is treated.

Waste water treatment- return flow

water returned to the environment by wastewater-treatment facilities.

Water activity: aw.

Qualitatively, aw is a measure of unbound, free water in a system, available to support biological and chemical reactions. Water activity affects microorganisms survival and reproduction, enzymes, and chemical reactions. The water activity of a substance is quantitatively equal to the vapor pressure of the substance divided by the vapor pressure of pure water (both measured at the same temperature). Measurements range from 0.00 (dry) to 1.00 (pure water).

Water cycle

the circuit of water movement from the oceans to the atmosphere and to the Earth and return to the atmosphere through various stages or processes such as precipitation, interception, runoff, infiltration, percolation, storage, evaporation, and transportation.

Water phase salt

Measure of percent salt based on an analysis of the water phase of the tissue of a product, as opposed to the percent salt based on an analysis of the surface of a product. Used primarily in the fish industry.

Water potential

The physical property predicting the direction in which water will flow, governed by solute concentration and applied pressure.

Water quality

a term used to describe the chemical, physical, and biological characteristics of water, usually in respect to its suitability for a particular purpose.


the land area that drains water to a particular stream, river, or lake. It is a land feature that can be identified by tracing a line along the highest elevations between two areas on a map, often a ridge. Large watersheds, like the Mississippi River basin contain thousands of smaller watersheds.

Water table

the top of the water surface in the saturated part of an aquifer.

Water use

water that is used for a specific purpose, such as for domestic use, irrigation, or industrial processing. Water use pertains to human's interaction with and influence on the hydrologic cycle, and includes elements, such as water withdrawal from surface- and ground-water sources, water delivery to homes and businesses, consumptive use of water, water released from wastewater-treatment plants, water returned to the environment, and instream uses, such as using water to produce hydroelectric power.

Water-soluble vitamins

Nutrients that dissolve in water. These include vitamin C and the B vitamins.
Water-soluble vitamins can easily be lost in cooking if they are allowed to leach into the cooking water, which is then discarded. This problem can be avoided by serving foods raw, cooking foods in as little water as possible, or including the cooking water in the finished dish (e.g., in a soup or stew).

Watthour (wh)

an electrical energy unit of measure equal to one watt of power supplied to, or taken from, an electrical circuit steadily for one hour.

Wave guide

Physical component of a microwave system that guides the microwaves from magnetron to the cavity where the food is heated. When applied in the form of pulses, it reverses the charge for each pulse and pulse intensity gradually decreases.


The distance between crests of waves, such as those of the electromagnetic spectrum. A wavelength is the linear distance which is traversed by one complete wave cycle of electromagnetic energy.


A mathematical framework of signal analysis/synthesis.
This analysis is an extension of Fourier Analysis. Although the Fourier theory proves to be very successful in sciences and engineering, the "basis functions", or the basic vocabulary of Fourier Analysis, are very large (as large as the stimulus/object itself), making them difficult to use in some context and unrealistic as the building block of the visual system. Wavelet Theory, meaning the theory of small waves, uses spatially localized images as its building block and is more useful than Fourier Analysis in some areas of visual neuroscience. The Gabor wavelet is very widely used as stimulus in visual physiology.

Weak electrolyte

A substance that only partially ionizes in aqueous solution.

Wechsler Intelligence Scales/Tests:

Any of of a series of verbal and performance Weschler tests widely used in school systems. These include: Weschler Preschool and Primary Scale of Intelligence (WPPSE), Wechsler Intelligence Scale for Children (WISC), Wechsler Intelligence Scale for Children (Revised) (WISC-R), and Wechsler Adult Intelligence Scale (Revised) (WAIS-R).


1. The force on an object due to the gravitational pull of a planet or other heavenly body.
2. In research, a number associated with a case or unit of analysis; the weight is used as a measure of the relative significance of the variables of that case when making estimates for the entire population.
Weighting is a mathematical process which allows individual values in a data set to be given greater or less impact in an equation than their values alone would contribute When a probability sample is used, there is often a chance that some elements of the population are under or over represented in the sample. In order to allow more accurate estimates of a complete population, therefore, "weights" are assigned to each case and used to adjust the overall results to more closely conform to the total population.  Thus, a weight is a mechanism of allocating confidence or strength to  data point, i.e., it’s a way of something how much confidence yo can place in that vale. If you don’t allocate any weights to a set of data, in effect you’re saying they all have equal weight (a weight say of 1) and that they are all equally reliable.

Western blots

A technique for visualization of antibodies directed against viral proteins that have been separated using some form of gel electrophoresis. A technique for analyzing mixtures of proteins to show the presence, size and abundance of one particular type of protein. Similar to Southern or Northern blotting (see "Blotting"), except that (1) a protein mixture is electrophoresed in an acrylamide gel, and (2) the "probe" is an antibody which recognizes the protein of interest, followed by a radioactive secondary probe (such as 125I-protein A).
For WB analysis sufficiently separated proteins on an SDS-PAGE gel are transferred to a solid membrane using an electric current applied to the gel so that the separated proteins transfer through the gel and onto the membrane in the same pattern as they separated on the SDS-PAGE. All sites on the membrane which do not contain blotted protein from the gel can then be non-specifically "blocked" so that antibody (serum) will not non-specifically bind to them, causing a false positive result. Often the membrane is cut into strips to facilitate testing of a large number of samples for antibodies directed against the blotted protein (antigen).
To detect the antigen blotted on the membrane, a primary antibody (serum) is added at an appropriate dilution and incubated with the membrane. If there are any antibodies present which are directed against one or more of the blotted antigens, those antibodies will bind to the protein(s) while other antibodies will be washed away at the end of the incubation. In order to detect the antibodies which have bound, anti-immunoglobulin antibodies coupled to a reporter group such as the enzyme alkaline phosphatase are added (e.g. goat anti-human IgG- alkaline phosphatase). This anti-Ig-enzyme is commonly called a "second antibody" or "conjugate". Finally after excess second antibody is washed free of the blot, a substrate is added which will precipitate upon reaction with the conjugate resulting in a visible band where the primary antibody bound to the protein. (see Electrophoresis and SDS-PAGE electrophoresis)

White Noise

A signal made up by mixing waves of all frequencies, with equal energy at all frequencies. (In practise this may often mean all frequencies in the audible range or all frequencies in the visible range).
The "White" part of the word comes from white light. A white light is a light consisting of electromagnetic waves of all frequencies. White noise is a signal consisting of waves of all frequencies with equal energy at all frequencies; thus a plot of the energy distribution across the frequency spectrum is a flat line (i.e., its power density is constant over the finite frequency range). It is therefore a form of signal of "no statistical structure" that can be easily implemented in labs, making it a widely used stimulus in neurophysiology.
Physiologists sometimes put different weights on different frequencies so that the signal is no longer pure white noise (equal energy at all frequencies). This type of signal is called coloured noise (see Noise signals).

Whole cell configuration for patch clamp recordings

See Patch clamp recordings

Whole numbers

The set of numbers that includes zero and all of the natural numbers.

Wild type (wt)

A term referring to the natural genetic form of an organism; An individual with the normal phenotype. A wild type is distinguished from a mutant form (an organism with a genetic mutation) usually based on a single mutation. Note, that within a population of an organism, there is no such thing as a wild type. The term, however, is useful for genetic manipulation studies because it allows a simple definition of a standard or control condition.

Wilm’s tumour

A childhood kidney cancer caused by the inactivation of a tumour suppressor gene.


The term can refer to thin diameter, fully flexible wires with minimal resistance to bending or thicker diameter wires, such as K-wires, that can be used as rigid fixation devices.

Withdrawing behaviour

Behavior characterized by reduced interest in or contact with other people, and can include absence of speech, regression to babyhood, exhibition of many fears, depression, and refusing contacts with other people.

Within-animal design

An experimental design in which each animal acts as its own control.
In these experiments data are collected for a control condition and for an experimental condition from the same animal(s).  In addition to minimising the use of animals (since separate control and experimental animals are not required), this design also controls for inter-animal variation in responsiveness due to physiological or experiential differences between animals.


A violation of the base-pairing rules in that third nucleotide (5' end) of a tRNA anticodon can form hydrogen bonds with more than one kind of base in the third position (3' end) of a codon. The ability of certain bases at the third position of an anticodon in tRNA to form hydrogen bonds in various ways, causing alignment with several possible codons.
Referring to the reduced constraint of the third base of an anticodon as compared with the other bases thus allowing additional complementary base pairing.


Hard, inanimate object that you throw at a wabbit.


The amount of energy transferred to a system.